Image sensors have become ubiquitous. They are widely used in digital still cameras, cellular phones, security cameras, as well as, medical, automobile, and other applications. The technology used to manufacture image sensors has continued to advance at a great pace. For example, the demands of higher resolution and lower power consumption have encouraged the further miniaturization and integration of these devices.
To differentiate between colors image sensors may use color filters. Color filters filter incident light on the image sensor by wavelength range, so that each photodiode in the image sensor only receives image light in a particular wavelength range. The raw data captured by the image sensor is converted into a full color image by a demosaicing algorithm which is tailored for the various color filters.
While there are a variety of ways to make color image sensors, reducing the number of steps in semiconductor processing applications is always important. Since every fabrication step adds cost and time on the assembly line, new techniques to enhance image sensor throughput are needed.
Corresponding reference characters indicate corresponding components throughout the several views of the drawings. Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention.